Structural durability reliability assessment should be based on the system and should also reflect the characteristics of the structural properties and dynamic time-varying characteristics. In this paper, based on Bayesian dynamic updating, taking the depth of concrete carbonization as a random variable, the traditional static carbonization model is modified based on the real bridge detection information that reflects the structural personality characteristics. Taking the reliability index as the evaluation standard, a differential equivalent recursive algorithm that can be included in the correlation between components is introduced and embedded in the Bayesian dynamic update framework. The dynamic evaluation model and calculation process of carbonization durability of the system are proposed, and the dynamic reliability calculation method of carbonization durability of complex system is put forward. The calculation program is developed based on MATLAB platform. The dynamic durability evaluation of the reinforced concrete arch bridge was carried out by carbonation simulation tests. Results show that the reliability of carbonization durability of the arch ring and the column increased while the reliability of carbonization durability of bridge deck decreased via the modified model. The durability of the system is lower than the reliability of the component.